. >> we gave her about 60 unitsofnarcan. >>also known as noloxan, can reverse an overdose from heroin and other drugs, like oxycodone. another sternal rub, another shot of narcan. >> giving her the rest. >> and finally, liz begins to come to. >> liz? are you okay? you went out. we gave you mouth-to-mouth resuzitation. some narcan. you overdosed. can you sit up? all right, come on. >> when someone takes heroin, the drug locks on to receptors in the brain. it slows the body down. lock up too many and you stop breathing. nalozone can free up the receptors, essentially bringing you back to life. you might wonder, that video of liz, is that real? we showed it to four emergency room doctors who said yes, this is what a recovery with narcan looks like. >> i can't believe that somebody cared about me enough or, you know, loved me enough to bring me back. >> back to right a light that somehow went wrong. we met liz on the day she went to rehab, packing up her things, looking at the album of her 19-month-old daughter. >> i felt so separated and disassociated from my daughter because i felt like